This publication presents the application of Non-Linear Programming (NLP) to the design of AC induction motors driving hydraulic pumps on commercial aircrafts. In addition to the usual constraints on the geometry or on the efficiency of the motor, the specifications for this application include conditions on the supply frequency, environment temperature and in-rush current, which are very difficult to meet. The NLP had to be adapted to support constraints on multiple operating points of the motor. A prototype of the motor has been built and the theory has been validated with practical results.